DSA Solutions
LeetCode problems explained in detail. Java implementations with complexity analysis.
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LeetCode Activity
Live problem-solving proof.
Public LeetCode activity, recent accepted problems, and topic coverage from @hs913271.
335
Total solved
48
Current streak
113
Active days
Recent solved
Latest 5 acceptedActivity graph
Last 26 weeksLessMore
Topic coverage
Problems solved by skill areaAdvanced
Dynamic Programming63
Backtracking10
Divide and Conquer9
Union-Find8
Monotonic Stack8
Topological Sort5
Monotonic Queue4
Data Stream2
Intermediate
Hash Table73
Math54
Depth-First Search39
Breadth-First Search39
Greedy36
Tree28
Binary Search28
Binary Tree24
Fundamental
Array195
String74
Sorting42
Matrix31
Two Pointers27
Simulation25
Stack25
Linked List19
#3629
MediumMinimum Jumps to Reach End via Prime Teleportation
ArrayBreadth-First SearchMathNumber Theory
#3660
MediumJump Game IX
ArrayStackMonotonic StackGraph
#1861
MediumRotating the Box
ArrayMatrixSimulation
#61
MediumRotate List
Linked ListTwo Pointers
#396
MediumRotate Function
ArrayMathDynamic Programming
#3225
HardMaximum Score From Grid Operations
ArrayDynamic ProgrammingMatrixPrefix Sum
#2033
MediumMinimum Operations to Make a Uni-Value Grid
ArrayMathSortingMatrix
#1391
MediumCheck if There is a Valid Path in a Grid
ArrayDepth-First SearchBreadth-First SearchUnion FindMatrix
#1559
MediumDetect Cycles in 2D Grid
ArrayDepth-First SearchBreadth-First SearchUnion FindMatrix
#3464
HardMaximize the Distance Between Points on a Square
ArrayBinary SearchGreedyGeometry
#2615
MediumSum of Distances
ArrayHash TablePrefix Sum
#2452
MediumWords Within Two Edits of Dictionary
ArrayString
#1722
MediumMinimize Hamming Distance After Swap Operations
ArrayHash TableDepth-First SearchBreadth-First SearchUnion Find
#2078
EasyTwo Furthest Houses With Different Colors
Array
#3783
EasyMirror Distance of an Integer
Math
#3761
MediumMinimum Absolute Distance Between Mirror Pairs
ArrayHash TableMath
#3488
MediumClosest Equal Element Queries
ArrayHash TableBinary Search
#2515
EasyShortest Distance to Target String in a Circular Array
ArrayString
#2463
HardMinimum Total Distance Traveled
ArrayDynamic ProgrammingSorting
#1848
EasyMinimum Distance to the Target Element
Array
#3899
MediumAngles of a Triangle
ArrayMathGeometry
#3898
EasyFind the Degree of Each Vertex
ArrayMatrixGraph
#3901
HardGood Subsequence Queries
ArrayNumber TheorySegment TreeMath
#3900
MediumLongest Balanced Substring After One Swap
StringHash TablePrefix Sum
#1320
HardMinimum Distance to Type a Word Using Two Fingers
StringDynamic Programming
#3741
MediumMinimum Distance Between Three Equal Elements II
ArrayHash Table
#3740
EasyMinimum Distance Between Three Equal Elements I
ArrayHash Table
#3653
MediumXOR After Range Multiplication Queries I
ArraySimulation
#3655
HardXOR After Range Multiplication Queries II
ArrayMathDivide and Conquer
#2069
MediumWalking Robot Simulation II
ArrayMathDesignSimulation
#874
MediumWalking Robot Simulation
ArrayHash TableSimulation
#1185
EasyDay of the Week
Math
#657
EasyRobot Return to Origin
StringSimulation
#2
MediumAdd Two Numbers
Linked ListMathRecursion
#121
EasyBest Time to Buy and Sell Stock
ArrayDynamic Programming
#704
EasyBinary Search
ArrayBinary Search
#102
MediumBinary Tree Level Order Traversal
TreeBreadth-First SearchBinary Tree
#199
MediumBinary Tree Right Side View
TreeDepth-First SearchBreadth-First SearchBinary Tree
#70
EasyClimbing Stairs
MathDynamic ProgrammingMemoization
#133
MediumClone Graph
Hash TableDepth-First SearchBreadth-First SearchGraph
#322
MediumCoin Change
ArrayDynamic ProgrammingBreadth-First Search
#11
MediumContainer With Most Water
ArrayTwo PointersGreedy
#217
EasyContains Duplicate
ArrayHash TableSorting
#207
MediumCourse Schedule
Depth-First SearchBreadth-First SearchGraphTopological Sort
#739
MediumDaily Temperatures
ArrayStackMonotonic Stack
#2075
MediumDecode the Slanted Ciphertext
StringMatrixSimulation
#150
MediumEvaluate Reverse Polish Notation
ArrayMathStack
#34
MediumFind First and Last Position of Element in Sorted Array
ArrayBinary Search
#153
MediumFind Minimum in Rotated Sorted Array
ArrayBinary Search
#733
EasyFlood Fill
ArrayDepth-First SearchBreadth-First SearchMatrix
#49
MediumGroup Anagrams
ArrayHash TableStringSorting
#198
MediumHouse Robber
ArrayDynamic Programming
#232
EasyImplement Queue using Stacks
StackDesignQueue
#57
MediumInsert Interval
ArrayIntervals
#226
EasyInvert Binary Tree
TreeDepth-First SearchBreadth-First SearchBinary Tree
#973
MediumK Closest Points to Origin
ArrayMathDivide and ConquerGeometrySortingHeap
#875
MediumKoko Eating Bananas
ArrayBinary Search
#215
MediumKth Largest Element in an Array
ArrayDivide and ConquerSortingHeapQuickselect
#230
MediumKth Smallest Element in a BST
TreeDepth-First SearchBinary Search TreeBinary Tree
#141
EasyLinked List Cycle
Hash TableLinked ListTwo Pointers
#14
EasyLongest Common Prefix
StringTrie
#1143
MediumLongest Common Subsequence
StringDynamic Programming
#300
MediumLongest Increasing Subsequence
ArrayBinary SearchDynamic Programming
#424
MediumLongest Repeating Character Replacement
Hash TableStringSliding Window
#3
MediumLongest Substring Without Repeating Characters
Hash TableStringSliding Window
#104
EasyMaximum Depth of Binary Tree
TreeDepth-First SearchBreadth-First SearchBinary Tree
#53
MediumMaximum Subarray
ArrayDynamic ProgrammingDivide and Conquer
#56
MediumMerge Intervals
ArraySortingIntervals
#21
EasyMerge Two Sorted Lists
Linked ListRecursion
#155
MediumMin Stack
StackDesign
#76
HardMinimum Window Substring
Hash TableStringSliding Window
#435
MediumNon-overlapping Intervals
ArrayDynamic ProgrammingGreedySortingIntervals
#200
MediumNumber of Islands
ArrayDepth-First SearchBreadth-First SearchUnion FindMatrix
#417
MediumPacific Atlantic Water Flow
ArrayDepth-First SearchBreadth-First SearchMatrix
#567
MediumPermutation in String
Hash TableTwo PointersStringSliding Window
#238
MediumProduct of Array Except Self
ArrayPrefix Sum
#19
MediumRemove Nth Node From End of List
Linked ListTwo Pointers
#143
MediumReorder List
Linked ListTwo PointersStackRecursion
#206
EasyReverse Linked List
Linked ListRecursion
#100
EasySame Tree
TreeDepth-First SearchBreadth-First SearchBinary Tree
#33
MediumSearch in Rotated Sorted Array
ArrayBinary Search
#347
MediumTop K Frequent Elements
ArrayHash TableBucket SortHeap
#125
EasyValid Palindrome
Two PointersString
#20
EasyValid Parentheses
StringStack
#98
MediumValidate Binary Search Tree
TreeDepth-First SearchBinary Search TreeBinary Tree
#139
MediumWord Break
Hash TableStringDynamic ProgrammingTrieMemoization
#3418
MediumMaximum Amount of Money Robot Can Earn
ArrayDynamic ProgrammingMatrix
#2751
HardRobot Collisions
ArrayStackSortingSimulation
#2840
MediumCheck if Strings Can be Made Equal With Operations II
StringHash TableCounting
#1
EasyTwo Sum
ArrayHash Table
#994
MediumRotting Oranges
ArrayBreadth-First SearchMatrix